Product Development through Advances in Materials Science at ECD/OBC

Advanced materials development has resulted in the commercialization of innovative new products at Energy Conversion Devices, Inc. such as thin-film amorphous silicon photovoltaic modules, nickel-metal hydride rechargeable batteries, phase change erasable optical memory disks, high-performance nonvolatile semiconductor memory devices, vapor barrier films for food packaging and long life electrophotographic photoreceptors. New materials have been engineered for these products through the use of chemical and structural disorder and unique processing technology has been developed to enable their manufacture. These advanced disordered materials range from multilayer thin film stacks of amorphous and microcrystalline silicon and amorphous silicon-germanium semiconductor alloys for solar cells, to thin film multielement chalcogenide (Te, Ge, Se, As) alloys for use in optical and electronic memories, to multiphase bulk hydride forming alloys such as VTiZrNiCrCoMnAlFe for use in nickel metal hydride rechargeable batteries. Processing technology for these materials ranges from RF glow-discharge and microwave plasma enhanced chemical vapor deposition for thin film semiconductor manufacturing to vacuum metallurgical bulk materials techniques utilizing induction melting, rapid solidification, hydrogen embrittlement and powder metallurgical processing. The materials, processing and commercialization status of each of these technologies is discussed, with particular emphasis on the NiMH battery.